The manipulation of ferrofluidic droplets by magnetic fields is a popular technique for controlling fluid transport in open microfluidic systems. We examine the effect of gravity and shear flow external forces on the adhesion properties of sessile ferrofluidic droplets in the presence of a uniform magnetic field. The magnetic field was found to enhance the critical Bond number at which sliding begins on a tilting substrate but suppress the critical Weber number at which sliding begins in a moderate Reynolds number channel flow.
View Article and Find Full Text PDFPreviously found effects of age on thresholds for speech reception thresholds in noise in adolescents as measured by an online screening survey require further study in a well-controlled teenage sample. Speech reception thresholds (SRT) of 72 normal-hearing adolescent students were analyzed by means of the online speech-in-noise screening tool Earcheck (In Dutch: Oorcheck). Screening was performed at school and included pure-tone audiometry to ensure normal-hearing thresholds.
View Article and Find Full Text PDFSurface coatings and patterning technologies are essential for various physicochemical applications. In this Letter, we describe key parameters to achieve uniform particle coatings from binary solutions. First, multiple sequential Marangoni flows, set by solute and surfactant simultaneously, prevent nonuniform particle distributions and continuously mix suspended materials during droplet evaporation.
View Article and Find Full Text PDFPurpose: There is a large body of evidence supporting the efficacy of low-level laser therapy (LLLT), more recently termed photobiomodulation (PBM) for the management of oral mucositis (OM) in patients undergoing radiotherapy for head and neck cancer (HNC). Recent advances in PBM technology, together with a better understanding of mechanisms involved and dosimetric parameters may lead to the management of a broader range of complications associated with HNC treatment. This could enhance patient adherence to cancer therapy, and improve quality of life and treatment outcomes.
View Article and Find Full Text PDFPurpose: There is a large body of evidence supporting the efficacy of low level laser therapy (LLLT), more recently termed photobiomodulation (PBM), for the management of oral mucositis (OM) in patients undergoing radiotherapy for head and neck cancer (HNC). Recent advances in PBM technology, together with a better understanding of mechanisms involved, may expand the applications for PBM in the management of other complications associated with HNC treatment. This article (part 1) describes PBM mechanisms of action, dosimetry, and safety aspects and, in doing so, provides a basis for a companion paper (part 2) which describes the potential breadth of potential applications of PBM in the management of side-effects of (chemo)radiation therapy in patients being treated for HNC and proposes PBM parameters.
View Article and Find Full Text PDFIn oral cancer treatment, function loss such as speech and swallowing deterioration can be severe, mostly due to reduced lingual mobility. Until now, there is no standardized measurement tool for tongue mobility and pre-operative prediction of function loss is based on expert opinion instead of evidence based insight. The purpose of this study was to assess the reliability of a triple-camera setup for the measurement of tongue range of motion (ROM) in healthy adults and its feasibility in patients with partial glossectomy.
View Article and Find Full Text PDFEur Arch Otorhinolaryngol
September 2016
The objective of this study is to assess surgical parameters correlating with voice quality after total laryngectomy (TL) by relating voice and speech outcomes of TL speakers to surgical details. Seventy-six tracheoesophageal patients' voice recordings of running speech and sustained vowel were assessed in terms of voice characteristics. Measurements were related to data retrieved from surgical reports and patient records.
View Article and Find Full Text PDFActa Otorhinolaryngol Ital
June 2015
This study investigated whether trachea pressures during brass instrument play of laryngectomised patients are within the range of those measured during tracheoesophageal voicing, and whether application of an automatic speaking valve can 'free' both hands to play a brass instrument. Objective assessment of voicing and music playing parameters was carried out in 2 laryngectomised patients with a low-pressure indwelling voice-prosthesis able to play brass instruments (tenor horn and slide trombone): sound pressure levels in dB, maximum phonation time in seconds and trachea pressures in mmHg; videofluoroscopy, stroboscopy and digital high speed endoscopy to assess neoglottis vibration and opening. The dynamic range of the voice in the patients was 29 and 20 dB, and maximum phonation time was 22 and 19 sec, respectively; intratracheal pressures during voicing varied from 7 mmHg for the softest /a/ to 49 mmHg for the loudest /a/.
View Article and Find Full Text PDFLiquid-infused surfaces display advantageous properties that are normally associated with conventional gas-cushioned superhydrophobic surfaces. However, the surfaces can lose their novel properties if the infused liquid drains from the surface. We explore how drainage due to gravity or due to an external flow can be prevented through the use of chemical patterning.
View Article and Find Full Text PDFRough or patterned surfaces infused with a lubricating liquid display many of the same useful properties as conventional gas-cushioned superhydrophobic surfaces. However, liquid-infused surfaces exhibit a new failure mode: the infused liquid film may drain due to an external shear flow, causing the surface to lose its advantageous properties. We examine shear-driven drainage of liquid-infused surfaces with the goal of understanding and thereby mitigating this failure mode.
View Article and Find Full Text PDFThe aim of this study was to investigate to what extent changes in speech after C-IMRT treatment are related to mean doses to the tongue and velopharynx (VP). In 34 patients with advanced hypopharyngeal, nasopharyngeal, or oropharyngeal cancer, changes in speech from pretreatment to 10 weeks and 1 year posttreatment were correlated with mean doses to the base of tongue (BOT), oral cavity (OC) and tonsillar fossa/soft palate (VP). Differences in anteroposterior tongue position, dorsoventral degree of tongue to palate or pharynx constriction, grooving, strength, nasality, and laryngeal rise, were assessed by acoustic changes in three speech sounds that depend on a (post-) alveolar closure or narrowing (/t/, /s/, /z/), three with a tongue to palate/pharyngeal narrowing (/l/, /r/, /u/), and in vowel /a/ at comfortable and highest pitch.
View Article and Find Full Text PDFWe study pressure and flow-rate fluctuations in microchannels, where the flow rate is supplied by a syringe pump. We demonstrate that the pressure fluctuations are induced by the flow-rate fluctuations coming from mechanical oscillations of the pump motor. Also, we provide a mathematical model of the effect of the frequency of the pump on the normalized amplitude of pressure fluctuations and introduce a dimensionless parameter incorporating pump frequency, channel geometry and mechanical properties that can be used to predict the performance of different microfluidic device configurations.
View Article and Find Full Text PDFConcurrent chemoradiotherapy (CCRT) for advanced head and neck cancer (HNC) is associated with substantial early and late side effects, most notably regarding swallowing function, but also regarding voice quality and quality of life (QoL). Despite increased awareness/knowledge on acute dysphagia in HNC survivors, long-term (i.e.
View Article and Find Full Text PDFObjectives: Our aim was to characterize articulation proficiency and differences between tumor sites before and after chemoradiotherapy for advanced head and neck cancer with the help of acoustic measures. Our further goal was to improve objective speech measures and gain insight into muscle functioning before and after treatment.
Methods: In 34 patients with laryngeal or hypopharyngeal, nasal or nasopharyngeal, or oral or oropharyngeal cancer, we acoustically analyzed nasality, vowel space, precision, and strength of articulation in 12 speech sounds (/a/, /i/, /u/, /p/, /s/, /z/, /1/, /t/, /tj/, /k/, /x/, /r/) before treatment and 10 weeks and 1 year after treatment.
Objectives/hypothesis: Assessment of a novel adhesive baseplate (Provox StabiliBase) for heat and moisture exchanger (HME) and/or automatic speaking valve (ASV) application.
Study Design: Prospective, clinical, multicenter trial.
Methods: This was a trial in laryngectomized patients comparing their usual adhesive with the trial adhesive.
Objectives: Perceptual judgments and patients' perception of voice and speech after concurrent chemoradiotherapy (CCRT) for advanced head and neck cancer.
Study Design: Prospective clinical trial.
Methods: A standard Dutch text and a diadochokinetic task were recorded.
Objective: To assess the endotracheal temperature and humidity and clinical effects of 2 models of a new heat and moisture exchanger (HME): Rplus, which has regular breathing resistance, and Lplus, which has lower breathing resistance.
Methods: We measured endotracheal temperature and humidity in 10 laryngectomized patients, for 10 min each, with and without the HMEs. We sequentially tested 4 HME models (all Atos Medical, Hörby, Sweden), in randomized order: Rplus, Lplus, Provox Normal (the HME we regularly use and which we considered the reference HME), and Stomvent (an older HME model).
Purpose of this review is to systematically assess the effects on voice and speech of advanced head and neck cancer and its treatment by means of chemoradiotherapy (CRT). The databases Medline, Embase and Cochrane were searched (1991-2009) for terms head and neck cancer, chemoradiation, voice and speech rehabilitation. Twenty articles met the inclusion criteria, whereof 14 reported on voice outcomes and 10 on speech.
View Article and Find Full Text PDFObjectives/hypothesis: To assess device life of the new Provox Vega 22.5 and 20 Fr prostheses, to establish whether the optimized airflow characteristics of these devices materialize in better voice characteristics in comparison to Provox2, and to assess the feasibility of voice prosthesis replacement with the new Smart Inserter.
Study Design: Prospective clinical phase II study.
Conclusion: Both the regularly used heat and moisture exchanger (R-HME) and the HME with both an antimicrobial and hygroscopic element (F-HME) are effective moisture exchangers. The antimicrobial filter of the F-HME acts as a heat exchanger. The external features of the F-HME were experienced as inconvenient, but decreased sputum production was reported as well.
View Article and Find Full Text PDFConclusions: Provox Vega prostheses demonstrate good short-term feasibility, and their optimized airflow-resistance design offers laryngectomy patients indwelling voice prostheses with more choices in outer diameters without sacrificing (too) much in voice quality.
Objectives: Technological progress enables improvement of in vitro airflow characteristics of voice prostheses and design of voice prostheses with smaller outer diameters. This could potentially improve voice quality in users of Provox2, and avoid diminished voice quality in users of prostheses with smaller outer diameters.
Background: Breathing in patients with obstructive sleep apnea (OSA) is frequently interrupted by periods of hypopnea and apnea. There is limited information regarding a possible disturbance of breathing outside these periods.
Study Objective: To analyze the degree of breathing disturbance during nonocclusion.
Vinorelbin is an important tumouricidal substance. The (cardio-)vascular side effects are not well known. We report on four patients in highly palliative situations who were treated with vinorelbine for non-small cell lung cancer.
View Article and Find Full Text PDFDrug Discov Today
March 2000
Sequencing of bacterial genomes has been progressing with breathtaking speed. Currently, the genomes of 23 bacterial species are sequenced, with approximately 40 more sequencing projects in progress. Industrial research is now facing the challenge of translating this information efficiently into drug discovery.
View Article and Find Full Text PDFThe thrombin-like serine protease ancrod from the Malayan pit viper Agkistrodon rhodostoma was expressed in mouse epithelial cells (C127). Oligosaccharide constituents were liberated from tryptic glycopeptides by treatment with peptide-N4-(N-acetyl-beta-glucosaminyl) asparagine amidase F. Neutral oligosaccharide alditols obtained after reduction and enzymic desialylation were separated by two-dimensional HPLC and characterized by methylation analysis, liquid secondary-ion mass spectrometry, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and sequential degradation with exoglycosidases.
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